p53 and c-erbB-2 protein expression in adenocarcinomas and epithelial dysplasias of the gall bladder

Utility of IMP3, p53, and S100P immunohistochemical stains in distinguishing reactive atypia from dysplasia in cholecystectomy specimens

BACKGROUND

Distinguishing reactive atypia from dysplasia in cholecystectomy specimens can be histologically challenging. The aim of this study was to evaluate the utility of IMP3, p53, and S100P immunostains in differentiating reactive atypia from dysplasia in cholecystectomies.

METHODS

Fifty-four cholecystectomies were reviewed and characterized into 5 groups: 2 normal, 29 reactive atypia, 16 low-grade dysplasia, 2 high-grade dysplasia, and 5 adenocarcinoma. IMP3, p53, and S100P immunostains were performed and evaluated. IMP3 (nuclear) and S100P (nuclear or nuclear/cytoplasmic) were categorized into negative or positive expression, and p53 was categorized into wild-type and aberrant/mutant expression. Chi-square test was used for statistical analysis.

RESULTS

The patients were mostly middle-aged women (mean 44, range 19-87 years, 81% female), with predominantly Hispanic White ethnicity (80%). The majority of the normal and reactive atypia cases showed negative IMP3 (100% and 75.9%, respectively) and wild-type p53 (100% and 89.7%, respectively) staining. Over half (56.3%) of the low-grade dysplasia and all the high-grade dysplasia cases showed IMP3 positivity. Aberrant p53 staining pattern was seen in half of both low and high-grade dysplasia cases. Adenocarcinoma showed IMP3 positivity in 80% and p53 aberrancy in all cases. S100P showed no statistical significance among the diagnostic categories. Significant differences in staining patterns were found between reactive atypia vs. low-grade dysplasia, and reactive atypia vs. low-grade + high-grade dysplasia using a combination of IMP3 and p53 stains (all p < 0.05).

CONCLUSIONS

In challenging cholecystectomies, IMP3 positivity or aberrant p53 expression may serve as a useful adjunct to support a diagnosis of dysplasia over reactive atypia.

Gallbladder Clear Cell Carcinoma: Report of a Rare Case and Literature Review

Carcinoma of the gallbladder is the most common biliary tract cancer. The majority of gallbladder cancers are adenocarcinomas, whereas clear-cell carcinoma of the gallbladder (CCG) is a rarely recorded variant. Usually, diagnosis is established incidentally after cholecystectomy, performed for another reason. Clinically, the different histological types of carcinomas are impossible to be recognized preoperatively, since they present with a wide and common range of symptoms. We present a male patient who underwent an emergency cholecystectomy due to suspected perforation. After an uneventful postoperative period, the histopathological report led to the diagnosis of CCG, but the surgical margins were infiltrated by the tumor. The patient decided not to proceed with any additional treatment and passed away 8 months after the operation. In conclusion, it is of great necessity to record such unusual cases and enriches global knowledge with information clinically and educationally noteworthy.

Incidence, Mortality, and Survival Trends in Cancer of the Gallbladder and Extrahepatic Bile Ducts in Lithuania

Background and Objectives: Gallbladder cancer is a rare type of cancer, with aggressive clinical behavior. Limited treatment options provide poor survival prognosis. We aimed to investigate the incidence, mortality trends, and survival of gallbladder and extrahepatic bile duct cancer in Lithuania between 1998 and 2017. Materials and Methods: The study was based on the Lithuanian Cancer Registry database. The study included all cases of cancer of the gallbladder and extrahepatic bile ducts reported to the Registry in the period 1998–2017. Age-specific and age-standardized incidence rates were calculated. In addition, 95% confidence intervals for APC (Annual Percent Change) were calculated. Changes were considered statistically significant if p was <0.05. Relative survival estimates were calculated using period analysis according to the Ederer II method. Results: Age-standardized rates for gallbladder cancer and extrahepatic bile duct cancer among females decreased from 3.91 to 1.93 cases per 100.000 individuals between 1998 and 2017, and from 2.32 to 1.59 cases per 100.000 individuals between 1998 and 2017 among males. The highest incidence rates were found in the 85+ group with 27.5/100,000 individuals in females and 26.8/100,000 individuals in males. The 1-year as well as 5-year relative survival rates of both genders were 34.29% (95% CI 32.12–36.48) and 16.29% (95% CI 14.40–18.27), respectively. Conclusions: Incidence and mortality from gallbladder and extrahepatic bile duct cancer decreased in both sexes in Lithuania. Incidence and mortality rates were higher in females than in males. Relative 1-year and 5-year survival rates showed a steady increase during the study period among males and females.

Screening and identification of haptoglobin showing its important role in pathophysiological process of gallbladder carcinoma

Gallbladder cancer (GBC) with poor prognosis has been a major cause of cancer-related deaths worldwide. In this study, we aimed to screen and identify crucial genes in GBC through integrative analysis of multiple datasets and further experimental validation. A candidate crucial gene, up-regulated haptoglobin (HP), was firstly screened, and then further analysis and validation mainly focused on whether higher enrichment level of HP was responsible for pathophysiological process of GBC. HP was found with diverse expression patterns in various cancer types, and the dynamic expression patterns indicated its spatiotemporal characteristics in different tissues and disease stages, implicating its role in multiple biological processes. Further experimental validation showed that HP could promote the GBC-SD cell proliferation, migration and invasion, implying its role in pathophysiological process of GBC. HP may have a crucial role in occurrence and development of GBC, and it provides possibility as a potential biomarker or target in cancer prognosis and treatment.

Molecular pathways and potential biomarkers in gallbladder cancer: A comprehensive review

The most common malignancy of the biliary tract, gallbladder cancer (GBC) often has a dismal prognosis. The aggressive nature of the tumor, delayed diagnosis at advanced stages of the disease, and lack of effective treatment options are some of the factors that contribute to a poor outcome. Early detection and accurate assessment of disease burden is critical to optimize management and improve long-term survival, as well as identify patients for adjuvant therapy and clinical trials. With recent advances in the understanding of the molecular pathogenesis of GBC, several specific diagnostic and biomarkers have been proposed as being of diagnostic and prognostic importance. Indeed, identification of novel diagnostic and prognostic markers has an important role in early diagnosis and development of targeted therapies among patients with GBC. Next-generation sequencing technology and genomewide data analysis have provided novel insight into understanding the molecular pathogenesis of biliary tract cancers, thereby identifying potential biomarkers for clinical use. We herein review available GBC biomarkers and the potential clinical implications in the management of GBC.

HER2/HER3 pathway in biliary tract malignancies; systematic review and meta-analysis: a potential therapeutic target?

Human epidermal growth factor receptor 2 (HER2) overexpression and amplification have been reported as predictive markers for HER2-targeted therapy in breast and gastric cancer, whereas human epidermal growth factor receptor 3 (HER3) is emerging as a potential resistance factor. The aim of this study was to perform a systematic review and meta-analysis of the HER2 and HER3 overexpression and amplification in biliary tract cancers (BTCs). An electronic search of MEDLINE, American Society of Clinical Oncology (ASCO), European Society of Medical Oncology Congress (ESMO), and American Association for Cancer Research (AACR) was performed to identify studies reporting HER2 and/or HER3 membrane protein expression by immunohistochemistry (IHC) and/or gene amplification by in situ hybridization (ISH) in BTCs. Studies were classified as "high quality" (HQ) if IHC overexpression was defined as presence of moderate/strong staining or "low quality" (LQ) where "any" expression was considered positive. Of 440 studies screened, 40 met the inclusion criteria. Globally, HER2 expression rate was 26.5 % (95 % CI 18.9-34.1 %). When HQ studies were analyzed (n = 27 studies), extrahepatic BTCs showed a higher HER2 overexpression rate compared to intrahepatic cholangiocarcinoma: 19.9 % (95 % CI 12.8-27.1 %) vs. 4.8 % (95 % CI 0-14.5 %), respectively, p value 0.0049. HER2 amplification rate was higher in patients selected by HER2 overexpression compared to "unselected" patients: 57.6 % (95 % CI 16.2-99 %) vs. 17.9 % (95 % CI 0.1-35.4 %), respectively, p value 0.0072. HER3 overexpression (4/4 HQ studies) and amplification rates were 27.9 % (95 % CI 9.7-46.1 %) and 26.5 % (one study), respectively. Up to 20 % of extrahepatic BTCs appear to be HER2 overexpressed; of these, close to 60 % appear to be HER2 amplified, while HER3 is overexpressed or amplified in about 25 % of patients. Clinical relevance for targeted therapy should be tested in prospective clinical trials.

Gallbladder cancer epidemiology, pathogenesis and molecular genetics: Recent update

Gallbladder cancer is a malignancy of biliary tract which is infrequent in developed countries but common in some specific geographical regions of developing countries. Late diagnosis and deprived prognosis are major problems for treatment of gallbladder carcinoma. The dramatic associations of this orphan cancer with various genetic and environmental factors are responsible for its poorly defined pathogenesis. An understanding to the relationship between epidemiology, molecular genetics and pathogenesis of gallbladder cancer can add new insights to its undetermined pathophysiology. Present review article provides a recent update regarding epidemiology, pathogenesis, and molecular genetics of gallbladder cancer. We systematically reviewed published literature on gallbladder cancer from online search engine PubMed (http://www.ncbi.nlm.nih.gov/pubmed). Various keywords used for retrieval of articles were Gallbladder, cancer Epidemiology, molecular genetics and bullion operators like AND, OR, NOT. Cross references were manually searched from various online search engines (http://www.ncbi.nlm.nih.gov/pubmed,https://scholar.google.co.in/, http://www.medline.com/home.jsp). Most of the articles published from 1982 to 2015 in peer reviewed journals have been included in this review.

Report of a case with gallbladder carcinoma: P53 expression of the peritumor epithelium might predict biliary tract recurrence

INTRODUCTION

The over-expression of P53 protein in gallbladder carcinoma is a biomarker correlating with a poor survival. However, the significance of P53 expression in peritumor tissues is unknown. We experienced a case of gallbladder carcinoma where the operative specimen showed over-expression of P53 on the peritumor epithelium, and early recurrence developed at the biliary tract.

PRESENTATION OF CASE

A 74-year-old female patient was referred to our hospital due to wall thickening of the gallbladder on ultrasonography. Radiographic examinations revealed wall thickening at the fundus of gallbladder and no abnormalities of the biliary tract or surrounding lymph nodes. We performed open cholecystectomy and lymph node dissection without extrahepatic bile duct resection, as a frozen section of the surgical stump of the cystic duct was cancer-free. However, a pathological examination revealed over-expression of P53 protein in the epithelium of the peritumor to the cystic duct, which were diagnosed as normal on hematoxylin eosin staining. The patient developed bile duct metastases, two and half years after the operation. She underwent endoscopic stenting for the obstruction of bile duct with no additional therapy, and died 6 months later.

DISCUSSION AND CONCLUSION

The immunohistochemical staining of the GB wall or surgical stump for a surgical specimen of GBC may be crucial to predict the bile duct recurrence.

c-erbB-2 Oncoprotein Immunoreactivity in Gallbladder and Biliary Tract Cancers

Overexpression of c-erbB-2 protein, a 185-kD transmembrane tyrosine kinase protein, is found in a number of human cancers. c-erbB-2 expression was examined, using immunohistochemistry with the polyclonal antibody NCL-PC 11 in carcinoma of the gallbladder (n = 13), biliary tract (n = 6), and ampulla of Vater (n = 9). These were compared with nonmalignant conditions such as chronic cholecystitis (n = 1 1), gallbladder dysplasia (n = 3), and adenoma (n = 1), and ampullary carcinoma in situ (n = 3) and adenoma (n = 1). Most gallbladder carcinomas (85%) and dysplasias (100%), common bile duct (83%) and ampullary (67%) carcinoma, and ampullary carcinoma in situ (67%) showed moderate to strong c-erbB-2 protein immunoreactivity. In contrast, the majority of cases of chronic cholecystitis (64%) had absent or weak c-erbB-2 protein immunostaining. However, immunohistologic detection of c-erbB-2 overexpression in the form of distinct cell membrane immunostaining was found in a minority of gallbladder carcinomas (23%) and not in any of the other preneoplastic or neoplastic lesions of the biliary tract or chronic cholecystitis. The patients who had carcinoma with c-erbB-2 overexpression had a shorter median survival period (3.1 months). However, there was no correlation between tumor stage and c-erbB-2 expression. This may be related to the small number of cases of gallbladder tumors available for this study, and further work with a larger series with adequate clinical follow-up time may be required to confirm the prognostic trend. The differences in c-erbB-2 expression between gallbladder, common bile duct, and ampullary carcinomas suggest that mutation of the gene may be a late event in the sequential development of gallbladder and biliary tract cancers.

Evaluation of P53, E-cadherin, Cox-2, and EGFR protein immunoexpression on prognostic of resected gallbladder carcinoma

Background

Gallbladder carcinoma presents a dismal prognosis. Choice treatment is surgical resection that is associated a high levels of both morbidity and mortality. Best knowledgement of prognostic factors may result a better selection of patients either for surgical or multimodal treatment.

Aim

To evaluate tecidual immunoexpression of P53, E-cadherin, Cox-2, and EGFR proteins and to correlate these findings with resected gallbladder adenocarcinoma survival.

Methods

Clinical, laboratorial, surgical, and anatomopathological reports of a series of gallbladder adenocarcinoma patients were collected by individualized questionary. Total sample was 42 patients. Median of age was 72 years (35-87). There were seven men and 35 women. Lesion distribuition in according TNM state was the following: T1 (n=2), T2 (n=5), T3 (n=31), T4 (n=4). Twenty-three patients underwent radical resection (R0), while 19 palliative surgery (R1-R2). A block of tissue microarray with neoplasic tissue of each patient was confected. It was performed evaluation of P53, E-Caderine, COX-2, and EGFR proteins imunoexpression. These findings were correlated with overall survival.

Results

Five-year survival was 28%. The median of global survival was eight months. Only immunoexpression of EGFR protein was considered independent variable at multivariated analysis.

Conclusion

Final prognosis was influenced by over-expression of EGFR protein in tumoral tissue.

A genetic model for gallbladder carcinogenesis and its dissemination

Gallbladder cancer, although regarded as the most common malignancy of the biliary tract, continues to be associated with a dismal overall survival even in the present day. While complete surgical removal of the tumour offers a good chance of cure, only a fraction of the patients are amenable to curative surgery owing to their delayed presentation. Moreover, the current contribution of adjuvant therapies towards prolonging survival is marginal, at best. Thus, understanding the biology of the disease will not only enable a better appreciation of the pathways of progression but also facilitate the development of an accurate genetic model for gallbladder carcinogenesis and dissemination. This review provides an updated, evidence-based model of the pathways of carcinogenesis in gallbladder cancer and its dissemination. The model proposed could serve as the scaffolding for elucidation of the molecular mechanisms involved in gallbladder carcinogenesis. A better understanding of the pathways involved in gallbladder tumorigenesis will serve to identify patients at risk for the cancer (and who thus could be offered prophylactic cholecystectomy) as well as aid oncologists in planning the most suitable treatment for a particular patient, thereby setting us on the vanguard of transforming the current treatment paradigm for gallbladder cancer.

Mitotic count reflects prognosis of gallbladder cancer particularly among patients with T3 tumor

The surgical strategy for gallbladder cancer (GBC) depends on the extent of the disease. Thus, the identification of useful prognostic markers exerting strong prognostic impact for each T stage would be beneficial in the development of rational therapeutic strategies. The purpose of this study was to identify useful prognostic markers of GBC for each T stage. CD8⁺ tumor-infiltrating lymphocytes (TIL), Ki-67 labeling index (LI), p53 nuclear expression and mitotic count (MC) were investigated as candidate prognostic markers. In total, 86 patients with invasive GBC were included. Of the prognostic markers examined, only MC showed a correlation with reduced survival (P=0.0383) in the univariate analysis of overall T stage. In the univariate analysis of T2 stage (n=31), only high p53 expression correlated with survival showing a positive correlation (P=0.0154). In the univariate analysis of T3 stage (n=40), the only factor showing a significant correlation with survival was MC (P=0.0113). Multivariate analysis, including N and M as factors, identified only MC as an independent prognostic factor in T3 stage GBC (P=0.0419). In conclusion, this study demonstrated the strong prognostic impact of MC in GBC, particularly in patients with T3 tumor.

p53 and beta-catenin expression in gallbladder tissues and correlation with tumor progression in gallbladder cancer

BACKGROUND/AIM

The inactivation of the tumor suppressor gene and activation of the proto-oncogene are key steps in the development of human cancer. p53 and beta-catenin are examples of such genes, respectively. In the present study, our aim was to determine the role of these genes in the carcinogenesis of the gallbladder by immunohistochemistry.

PATIENTS AND METHODS

Sections from paraffin-embedded blocks of surgically resected specimens of gallbladder cancer (GBC) (80 cases), chronic cholecystitis (60 cases), and control gallbladders (10 cases) were stained with the monoclonal antibody p53, and polyclonal antibody beta-catenin. Results were scored semiquantitatively and statistical analysis performed. p53 expression was scored as percentage of the nuclei stained. Beta-catenin expression was scored as type of expression-membranous, cytoplasmic, and nuclear staining. Beta-catenin expression was correlated with tumor invasiveness, differentiation, and stage.

RESULTS

Over-expression of p53 was seen in 56.25% of GBC cases and was not seen in chronic cholecystitis or in control gallbladders. p53 expression in gallbladder cancer was significantly higher than in inflammatory or control gallbladders (P < 0.0001). p53 expression increased with increasing tumor grade (P = 0.039). Beta-catenin nuclear expression was seen in 75% cases of gallbladder cancer and in no case of chronic cholecystitis and control gallbladder. Beta-catenin nuclear expression increased with tumor depth invasiveness, and grade (P = 0.028 and P = 0.0152, respectively).

CONCLUSION

p53 and beta-catenin nuclear expression is significantly higher in GBC. p53 expression correlates with increasing tumor grade while beta-catenin nuclear expression correlates with tumor grade and depth of invasion, thus suggesting a role for these genes in tumor progression of GBC.

Expression of HER2 and bradykinin B1 receptors in precursor lesions of gallbladder carcinoma

AIM: To determine the expression of HER2 and bradykinin B₁ receptors (B₁R) in the two pathogenic models of gallbladder cancer: the metaplasia-dysplasia-carcinoma and the adenoma-carcinoma pathways.

METHODS: Receptor proteins were visualized by immunohistochemistry on 5-μm sections of paraffin-embedded tissue. Expression of both receptors was studied in biopsy samples from 92 patients (6 males and 86 females; age ranging from 28 to 86 years, mean 56 years). High HER2 expression in specimens was additionally investigated by fluorescence in situ hybridization. Cell proliferation in each sample was assessed by using the Ki-67 proliferation marker.

RESULTS: HER2 receptor protein was absent in adenomas and in normal gallbladder epithelium. On the contrary, there was intense staining for HER2 on the basolateral membrane of epithelial cells of intestinal metaplasia (22/24; 91.7%) and carcinoma in situ (9/10; 90%), the lesions that displayed a significantly high proliferation index. Protein up-regulation of HER2 in the epithelium with metaplasia or carcinoma in situ was not accompanied by HER2 gene amplification. A similar result was observed in invasive carcinomas (0/12). The B₁R distribution pattern mirrored that of HER2 except that B₁R was additionally observed in the adenomas. The B₁R appeared either as cytoplasmic dots or labeling on the apical cell membrane of the cells composing the epithelia with intestinal metaplasia (24/24; 100%) and carcinoma in situ (10/10; 100%) and in the epithelial cells of adenomas. In contrast, both HER2 (4/12; 33%) and B₁R (1/12; 8.3%) showed a low expression in invasive gallbladder carcinomas.

CONCLUSION: The up-regulation of HER2 and B₁R in precursor lesions of gallbladder carcinoma suggests cross-talk between these two receptors that may be of importance in the modulation of cell proliferation in gallbladder carcinogenesis.

A case of a choledochal cyst associated with a lymphatic infiltration of a hyperplastic gallbladder epithelium

A 4-year-old girl with a congenital choledochal cyst (Todani IV-A, Komi type A) underwent a resection of the dilated common bile duct and gallbladder. Histologic studies of the gallbladder showed a general hyperplastic change associated with cribriform proliferation at the gland base of the gallbladder. In this region, clusters of cribriform glands were found within the lymphatic vessels, compatible with lymphatic infiltration of tumor cells. However, careful histologic studies did not reveal any apparent neoplastic changes in the gallbladder and common bile duct, so a final diagnosis of epithelial atypism with reactive hypertrophy was made. The displacements observed in the lymphatics are just an incidental finding in a proliferative process of the hyperplastic gallbladder epithelium. In the follow-up observation for 3 years, the patient is doing well without evidence of tumor recurrence. These results suggest that a mere lymphatic infiltration of hyperplastic gallbladder epithelium should not be directly considered as evidence of carcinogenesis.

Gallbladder cancer: a morphological and molecular update

Gallbladder cancer (GBC) shows a marked geographical variation in its incidence, with the highest figures being seen in India and Chile and relatively low levels in many Western countries. Risk factors for its development include the presence of gallstones, infection and the presence of an anomalous pancreatobiliary ductal junction. It can arise from either a pathway involving metaplasia or dysplasia or one in which there is a pre-existing adenoma. The former is the more common and, because it is often not associated with a macroscopically recognizable lesion, leads to the recommendation that all gallbladders need to be examined microscopically. Accurate staging of invasive cancers is essential to determine prognosis and treatment, and this requires extensive tumour sampling. A number of genetic alterations have been identified in the preinvasive and invasive stages of GBC and they support the morphological evidence of there being two pathways by which tumours develop. Some of these genetic changes are associated with particular risk factors. For example, cases with anomalous pancreatobiliary ductal junction show a higher frequency of K-ras mutations. Some changes are associated with differences in prognosis. For example, cancers without expression of p21 but with expression for p27 have a better prognosis, whereas those that express c-erb-B2 have a worse one. Work has also been done on identifying clinical, imaging and other factors that indicate that patients have a higher risk of having GBC. This is particularly important in high-incidence areas in which GBC is a significant public health problem.

E1A, E1B double-restricted replicative adenovirus at low dose greatly augments tumor-specific suicide gene therapy for gallbladder cancer

Combination therapy with replicative oncolytic viruses is a recent topic in innovative cancer therapy, but few studies have examined the efficacy of oncolytic adenovirus plus replication-deficient adenovirus carrying a suicide gene. We aim to evaluate whether an E1A, E1B double-restricted oncolytic adenovirus, AxdAdB-3, can improve the efficacy for gallbladder cancers (GBCs) of the replication-deficient adenovirus-based herpes simplex virus thymidine kinase (HSVtk)/ganciclovir (GCV) therapy directed by the carcinoembryonic antigen (CEA) promoter. Cytopathic effects of AxdAdB-3 plus AxCEAprTK (an adenovirus expressing HSVtk directed by CEA promoter) or AxCAHSVtk (an adenovirus expressing HSVtk directed by a nonspecific CAG promoter) with GCV administration were examined in several GBC lines and normal cells. Efficacy in vivo was tested in severe combined immunodeficiency disease mice with GBC xenografts. Addition of AxdAdB-3 (1 multiplicity of infection, MOI) significantly enhanced the cytopathic effects of AxCEAprTK (10 MOI)/GCV on GBC cells. The augmented effect was attributable to the replication of the AxCEAprTK and also to the enhanced CEA promoter activity, which was presumably transactivated by E1A. In normal cells, AxdAdB-3 (20 MOI) plus AxCEAprTK (200 MOI)/GCV was not cytopathic, whereas AxdAdB-3 (1 MOI) plus AxCAHSVtk (10 MOI)/GCV was significantly toxic. Low-dose AxdAdB-3 (2 x 10(7) PFU, plaque-forming unit) plus AxCEAprTK (2 x 10(8) PFU)/GCV significantly suppressed the growth of GBC xenografts as compared with either AxdAdB-3 (2 x 10(7) PFU)/GCV or AxCEAprTK (2 x 10(9) PFU)/GCV alone. E1A, E1B double-restricted replicating adenovirus at low dose significantly augmented the efficacy of CEA promoter-directed HSVtk/GCV therapy without obvious toxicity to normal cells, suggesting a potential use of this combination for treating GBC and other CEA-producing malignancies.

Eosinophilic dysplasia of the gallbladder: a hitherto undescribed variant identified in association with a "porcelain" gallbladder

Non-mass forming, neoplastic intraepithelial proliferations (dysplasia) represent the most well-accepted precursor lesions to gallbladder adenocarcinomas. They are typically small, localized, grossly unrecognizable lesions that have been identified in the epithelium adjacent to up to 79% of gallbladder adenocarcinomas. Morphologic variants that have been reported include flat, micropapillary, papillary and cribriform. We have recently encountered a morphologically distinctive, previously unreported lesion to which we have applied the designation eosinophilic dysplasia. This lesion was identified in a gallbladder with diffuse mural fibrosis and calcification (porcelain gallbladder). The dysplastic focus was confined to one tissue section, and was comprised of a localized true papilla [i.e with a fibrovascular core], measuring approximately 1.2 mm in greatest dimension and an adjacent, flat, 7-cell epithelial segment. These foci were lined by cells displaying significant nuclear enlargement [1.5–4 times the adjacent benign cells], nuclear pleomorphism, occasional multinucleation, hyperchromasia and nuclear membrane irregularities. Nucleoli were present but inconspicuous. These cells also showed voluminous eosinophilic to granular cytoplasm, such that the overall nuclear-to-cytoplasmic ratio was generally not increased. The cells displayed diffuse and marked nuclear immunoreactivity for p53, and approximately 70% of the cells showed nuclear positivity for Ki-67. The cells were also positive for cytokeratin 7 and were entirely negative for carcinoembryonic antigen (CEA) and chromogranin A. The cells of the adjacent normal epithelium were positive for cytokeratin 7 and CEA, negative for p53 and chromogranin A and showed a Ki-67 labeling index of <10%. Marked overexpression of the p53 protein as well as its high proliferative index are strong arguments in favor of the dysplastic nature of this lesion. However, further studies are required to elucidate its true clinical significance and to determine whether or not its association with a porcelain gallbladder, as noted herein, is entirely fortuitous. However, such studies can only be performed with an increased recognition by practitioners of this distinctive variant.

Telomere length variation in biliary tract metaplasia, dysplasia, and carcinoma

Biliary tract carcinoma, including carcinoma of the gallbladder, intrahepatic bile ducts (cholangiocarcinoma), and extrahepatic bile ducts, affects 7500 people in the United States annually, and has an overall 32% 5-year survival rate for disease limited to the mucosa, and a dismal 10% 5-year survival for more advanced disease. The identification of factors involved in the pathogenesis and progression of biliary tract carcinoma is critical for devising effective methods of screening and treatment. Recent evidence suggests that reduction of the length of telomeres, which normally help maintain chromosomal stability, may promote the development and progression of a variety of carcinomas. Using a novel, recently validated telomere fluorescence in situ hybridization method, we examined telomere length in normal and inflamed gallbladder epithelium, metaplasia and dysplasia of the gallbladder, and biliary tract carcinoma to determine whether telomere shortening is associated with neoplastic progression in the biliary tract. Although normal and inflamed gallbladder epithelium demonstrated uniform normal telomere lengths, over half of all metaplastic lesions demonstrated shortened telomeres, supporting prior evidence that metaplastic lesions of the gallbladder are pre-neoplastic. Dysplastic epithelium and invasive carcinomas demonstrated almost universally abnormally short telomeres, indicating that telomere shortening occurs at an early, preinvasive stage of cancer development. In addition, invasive adenocarcinoma of the biliary tract frequently demonstrated intratumoral heterogeneity of telomere lengths. We conclude that telomere shortening is a consistent and early finding in the development of biliary tract carcinoma.

Preliminary study of p53 and c-erbB-2 expression in gallbladder cancer in Indian patients manuscript id: 8962091628764582

BACKGROUND

The inactivation of the tumour suppressor gene and activation of the proto-oncogene are the key steps in the development of the human cancer. The p53 and c-erbB-2 are the best examples of it. In the present study, our aim was to determine the role of these genes in the carcinogenesis of gallbladder by immunohistochemistry.

METHODS

In all 78 consecutive patients of gall bladder diseases were studied for p53 and c-erbB-2 expression immunohistochemically and their expression was correlated with the age, grades and stages of the disease and presence of stone. An informed consent was obtained in each case. Chi square and z test were applied to see the association of p53 and c-erbB-2 over expression with other clinicopathological factors.

RESULTS

Eight (20%) patients of gall bladder cancer were positive for p53 expression and 10 (25%) patients for c-erbB-2. The p53 positivity increased with increasing grade while cerbB-2 positivity decreased with increasing grade of gall bladder cancer. Mean age in cerbB-2 positive cases were lesser as compared to negative cases while p53 did not show such association with age.

CONCLUSION

Only one case of gall bladder cancer co-expressed the p53 and c-erbB-2, thereby suggesting that p53 and c-erbB-2 may have independent role in carcinogenesis of gall bladder cancer. c-erbB-2 over expression in adenoma and younger age group indicates its role as an early event in carcinogenesis of gallbladder. However study of larger sample is required to further validate the results.

Amplification and overexpression of c-erbB-2, epidermal growth factor receptor, and c-met in biliary tract cancers

Carcinomas of the biliary tract have a poor prognosis. It is important to understand the molecular genetic characteristics of these tumours in order to employ newer effective treatments and to improve patient prognosis. There is increasing evidence that overexpression of tyrosine kinase growth factor receptors such as ErbB-2, epidermal growth factor receptor (EGFR), and Met may play important roles in the development of biliary tract carcinomas. The aim of this study was to assess the potential for novel chemotherapies targeting these receptors. Overexpression of the tyrosine kinase receptor proteins was examined by immunohistochemistry in 221 biliary tract carcinomas, of which 28 were from the intrahepatic bile duct, 78 from the extrahepatic bile duct, 89 from the gall bladder, and 26 from the ampulla of Vater. Positively stained tumours were further examined for gene amplification by fluorescence in situ hybridization. Overexpression of ErbB-2 was found in 15.7%, 11.5%, and 5.1% of carcinomas of the gall bladder, ampulla of Vater, and extrahepatic bile duct, respectively, and gene amplification was present in 79% of these. Overexpression of EGFR was found in 8.1% of tumours with no predominant location and was also associated with gene amplification with high frequency (77%). Met overexpression, most frequent in intrahepatic bile duct carcinomas (21.4%), was not associated with gene amplification. It is proposed that the new adjuvant chemotherapies could be directed to carcinomas of the biliary tract in which ErbB-2 and EGFR are overexpressed.

Effective Gene Therapy of Biliary Tract Cancers by a Conditionally Replicative Adenovirus Expressing Uracil Phosphoribosyltransferase: Significance of Timing of 5-Fluorouracil Administration

In order to enhance the efficacy of conditionally replicating adenoviruses (CRAd) in the treatment of cancers of the biliary tract, we studied the efficacy in vitro and in vivo of AxE1CAUP, a CRAd vector that carries a gene for uracil phosphoribosyltransferase (UPRT), which converts 5-fluorouracil (5-FU) directly to 5-fluorouridine monophosphate and greatly enhances the cytotoxicity of 5-FU. AxE1CAUP replicated and induced an increased UPRT expression in biliary cancer cells more efficiently than AxCAUP, a nonreplicative adenovirus carrying the UPRT gene. Whereas AxCAUP and AxE1AdB, a CRAd without the UPRT gene, modestly increased the sensitivity of BC cells to 5-FU, AxE1CAUP markedly increased the sensitivity, especially when the timing of 5-FU administration was appropriately chosen. AxE1CAUP replicated much less efficiently in normal WI-38 fibroblasts without any change in the sensitivity to 5-FU. In nude mice with s.c. biliary cancer xenografts, i.t. AxE1CAUP/5-FU therapy inhibited tumor growth significantly more strongly than AxCAUP/5-FU or AxE1AdB/5-FU therapy. Furthermore, in mice with peritoneally disseminated biliary cancer, i.p. AxE1CAUP efficiently proliferated in the tumors, decreased the tumor burden, and prolonged the survival of the mice when 5-FU was started 10 or 15 days after the vector inoculation, whereas earlier initiation of 5-FU resulted in early eradication of the vector and no survival benefit. The present study shows that the CRAd expressing UPRT was a more potent sensitizer of biliary cancer to 5-FU, than was a nonreplicative UPRT-encoding vector or a CRAd without UPRT gene, even at a lower dose of the vector, and that timing of 5-FU administration was a key factor to maximize the efficacy. This gene therapy with appropriately timed administration of 5-FU should be useful in overcoming the resistance of biliary cancers to 5-FU.

Immunohistochemical study of microvessel density, CD44 (standard form), p53 protein and c-erbB2 in gallbladder carcinoma

BACKGROUND

The purpose of the present study was to investigate microvessel density (MVD), and the expression of CD44 adhesion molecule, p53 protein and c-erbB2 in gallbladder carcinoma, and their relation to histological grade and tumor invasiveness.

METHODS

Immunohistochemical staining with antibodies against factor VIIIRAg, CD44 standard form (CD44s), p53 protein and c-erbB2 was performed on paraffin sections from 33 cases of gallbladder carcinoma.

RESULTS

Significant increase of MVD with increasing depth of invasion (P < 0.02) was observed. No association of MVD with histological differentiation, CD44s, p53 and c-erbB2 protein expression was found. The expression of p53 protein was significantly higher in deeply invasive tumors (P = 0.028) and in moderately and poorly differentiated carcinomas (P < 0.05). The CD44s expression was higher in well-differentiated carcinomas (P < 0.05). c-erbB2 expression was found in 30.4% of tumors studied, but did not relate to any other parameters.

CONCLUSION

Microvessel density and p53 protein expression increase progressively with increasing tumor invasiveness in gallbladder carcinomas. Microvessel density, p53 protein, CD44s, and perhaps c-erbB2 expression may be implicated in gallbladder carcinoma evolution.

Gallbladder carcinoma: the role of p53 protein overexpression and Ki-67 antigen expression as prognostic markers

BACKGROUND

The overexpression of p53 protein and the expression of Ki-67 antigen may affect the survival of patients with gallbladder carcinoma. This association has been tested in a series of 41 patients with relatively early carcinoma of the gallbladder.

METHODS

Forty-one surgical specimens from patients with a postoperative histological diagnosis of gallbladder carcinoma were studied. All patients were operated by simple cholecystectomy only because the tumours were not advanced and/or their general condition was poor. Patients submitted to radical operations were excluded. p53 expression was calculated from nuclear staining according to the intensity and extent of positive cells, as graded on a scale from 1 to 3; a combined score of >3 was considered as overexpression. Ki-67 expression was calculated by the MIB-I index: the percentage of positively stained tumour cell nuclei out of the total tumour cells counted (n = 1000); >20% of stained cells was considered positive.

RESULTS

Twenty-nine gallbladder carcinomas (71%) overexpressed p53 protein in the cell nuclei. No significant differences were found in relation to cell differentiation on the level of tumour infiltration through the gallbladder wall. Five-year survival of patients with gallbladder carcinoma overexpressing p53 was 17.2%, while survival of patients without p53 overexpression was 30% (not significant). Twenty-four cases (58.5%) were considered positive for the MIB-I index. There were no differences between the grade of cell differentiation and wall infiltration. Five-year survival of the patients with a MIB-I positive index was 9.2% as opposed to 27.7% for those with a negative index (not significant).

CONCLUSIONS

p53 protein nuclear overexpression and Ki-67 protein expression in gallbladder carcinoma were not related to histological differentiation, level of gallbladder wall invasion or patient survival.

Gastric mucosa-associated lymphoid tissue lymphoma

The connection between Helicobacter pylori and gastric mucosa-associated lymphoid tissue (MALT) lymphoma is well established. H. pylori infection causes an immunological response, leading to chronic gastritis with formation of lymphoid follicles within the stomach. These lymphoid follicles resemble nodal tissues found throughout the body and are composed of reactive T cells and activated plasmal cells and B cells. The B cells are responsible for initiating a clonal expansion of centrocyte-like cells that form the basic histology of MALT lymphoma. Early diagnosis of MALT lymphoma is difficult but essential for adequate treatment. Clinical symptoms are vague and varied, with abdominal pain being a common presenting complaint. The endoscopic appearance of this tumor is varied and can be infiltrative, exophytic, or ulcerative. In addition, the tumor can have a multifocal distribution, and therefore aggressive tissue sampling is crucial for diagnosis. Endoscopic ultrasound is essential to document the extent of disease and is more accurate than CT scan in detection of spread to perigastric lymph nodes. Lesions that are confined to the mucosa or submucosa of the gastric wall are believed to be dependent on H. pylori stimulation and therefore can be successfully treated with H. pylori eradication. Those MALT lymphomas that present at more advanced stages require more aggressive management and can be treated with surgical resection, radiation, or chemotherapy. Follow-up is critical in all patients who have been treated with H. pylori eradication and consists of multiple endoscopic biopsies for histological and molecular studies as well as endoscopic ultrasound at 3, 6, and 12 months after treatment. The reappearance of MALT lymphomas has been seen years after treatment, and therefore follow-up of these patients should be indefinite.

Pancreaticobiliary maljunction: pathophysiological and clinical aspects and the impact on biliary carcinogenesis

BACKGROUND

Pancreaticobiliary maljunction (PBM) is frequently associated with congenital choledochal cyst (CCBD), but differs in embryonic cause and clinical features. It is thought to develop as a misarrangement of the embryonic connections in the pancreaticobiliary ductal system, with the terminal bile duct joined to one of the ducts of the ventral pancreas. Clinical aspects are intermittent abdominal pain, relapsing acute pancreatitis, jaundice, cholangitis, and gallbladder cancer. In patients with PBM and CCBD, primary bile duct stones, acute cholangitis, and bile duct cancer are considered to result from cholestasis, regurgitation of pancreatic juice, and reciprocal reflux of bile and pancreatic juice. The mixture of bile and pancreatic juice due to recipocal reflex very likely plays an important role in biliary carcinogenesis.

PATIENTS AND METHODS

We reviewed the pathophysiological and clinical aspects and biliary carcinogenesis in 250 PBM patients (169 with benign hepatobiliary and pancreatic disease, 81 with malignancy).

RESULTS

PBM patients show elevated cellular proliferation activity in the gallbladder epithelia. A number of oncogenes and tumor suppressor genes have been identified and implicated in carcinogenesis, particularly the K- ras oncogene and the p53 suppressor gene. Some K- ras mutations do not appear essential for hyperplasia but may be an early event in carcinogenesis. The p53 mutations are involved in carcinogenesis in the biliary epithelium in PBM patients.

Analysis of p53 and c-erbB-2 expression in ovarian endometrioid carcinomas arising in endometriosis

We assessed the immunohistochemical expression of p53 and c-erbB-2 oncoproteins in 13 ovarian endometrioid adenocarcinomas arising from endometriosis (group 1) and compared the findings with 15 otherwise similar cases without associated endometriosis (group 2). Tumors in group 1 showed a higher expression of both p53 and c-erbB-2 (p = 0.015 and p = 0.048, respectively). The expression of the two proteins was also significantly associated in group 1 (p = 0.013) but not in group 2 (p = 0.63) tumors. The different pattern of expression of p53 and c-erbB-2 in the two groups suggests that different molecular pathways may be involved in their pathogenesis.

Significance of contracted cholecystitis lesions as high risk for gallbladder carcinogenesis

A precancerous change has been identified incidentally in resected specimens from patients who have undergone cholecystectomy. We focused on chronic cholecystitis, showing a thick and sclerotic wall caused by recurrent inflammation, e.g. contracted cholecystitis, and examined the malignant potential of these lesions. We studied 88 patients who had undergone cholecystectomy. Contracted cholecystitis was diagnosed, using our criteria, in 28 of these cases. Ordinary chronic cholecystitis was diagnosed in 50 cases and gallbladder carcinoma in ten cases. We examined the expression of p53, Ki-67, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) immunohistochemically. Severe dysplasia or carcinoma in situ in a very small portion of the specimen was identified with hematoxylin-eosin staining in four cases (14.3%) of contracted cholecystitis. These specimens revealed a positive expression of not only p53, but also Ki-67, iNOS, and COX-2. Statistical significance was shown among the three disease groups in terms of the incidence of p53 overexpression, respectively (P<0.05). The results of this study suggest that contracted cholecystitis could be an early change leading to carcinogenesis.

Genetic alterations in gallbladder adenoma, dysplasia and carcinoma

Adenoma and dysplasia in the gallbladder (GB) have been reported as precancerous lesions, but the genetic evidence of this is not clearly defined. The purpose of this study was to analyze the frequencies of K-ras, p53, and p16 gene mutations, of microsatellite instability (MI) and of loss of heterozygosity (LOH) in GB cancer, dysplasia, and adenoma. Tissues from 15 GB cancers, five dysplasias around cancerous tumors, and three adenomas were collected prospectively. The mutation rates of K-ras, p53, and p16 were 20.0, 35.7, and 30.7%, respectively, in GB cancers. However, no mutations were found in dysplasia or adenoma. Reduced staining for p16 was seen in 23% of carcinomas. All of the GB carcinomas and four out of five (80%) of the dysplasias showed LOH in a minimum of one locus, but one out of three (33%) cases of adenoma displayed LOH in only one locus. All of the loci of LOH in the dysplasias, except one, showed the same patterns of allelic loss as the adjacent carcinomas. Only one dysplasia showed multiple MI. In conclusion, multiple LOH may be associated with the development of dysplasia and the malignant transformation of GB carcinoma. Gene alterations of K-ras, p53, and p16 are important steps in the malignant changes of dysplasia. However, MI seems to have only a limited role in GB cancer development.

p27(Kip1) expression in normal epithelia, precancerous lesions, and carcinomas of the gallbladder: association with cancer progression and prognosis

p27(Kip1) is a cyclin-dependent kinase inhibitor that negatively regulates cell proliferation. This study was designed to evaluate the roles of p27(Kip1) in gallbladder carcinogenesis and the prognostic value of p27(Kip1) in patients with gallbladder carcinoma. p27(Kip1) expression was examined immunohistochemically in surgically resected specimens of 8 normal epithelia, 8 adenomyomatosis lesions, 6 precancerous adenomas, and 37 carcinomas of the gallbladder. Decreased p27(Kip1) expression (<50% nuclear staining) was observed in 16 of the 37 (43%) gallbladder carcinomas, but not in any specimen of normal epithelium, adenomyomatosis, or adenoma. The fact that all of the adenomas showed normal p27(Kip1) expression suggests that decreased p27(Kip1) expression is probably not an early event in gallbladder carcinogenesis. Decreased p27(Kip1) expression was significantly associated with less marked tumor cell differentiation (P =.017), lymphatic invasion (P =.046), lymph node metastasis (P =.007), and advanced TNM stage (stage IV vs. stage I, P =.026; stage IV vs. stage II, P =.005). This suggests that down-regulation of p27(Kip1) expression is a late event in gallbladder carcinogenesis, possibly promoting tumor progression and metastasis. Kaplan-Meier curves showed that decreased p27(Kip1) expression was significantly associated with shorter overall survival (P =.001) in patients with gallbladder carcinomas who had undergone radical surgery. Cox's proportional hazards model revealed decreased p27(Kip1) expression to be an independent predictor for death (P =.034; risk ratio, 3.9; 95% confidence interval, 1.1-13.7). In conclusion, decreased p27(Kip1) expression significantly correlates with tumor progression and predicts poor prognosis in gallbladder carcinomas.

Overexpression of p53 protein in gallbladder carcinoma in North India

AIMS

p53 mutations are one of the most frequent genetic alterations in human cancers and are thought to play a role in pathogenesis of several malignancies. Overexpression of p53 in gallbladder cancer has not previously been reported from North India which has one of the highest incidence of this malignancy in the world. The present work is aimed at studying the overexpression of p53 in gallbladder carcinoma occurring in North India.

METHODS

p53 overexpression by immunohistochemistry was studied in 20 operative specimens of gallbladder carcinoma. The clinico-pathological observations of these patients were correlated with the extent of p53 overexpression.

RESULTS

Seventy per cent (14/20) of specimens of gallbladder carcinoma overexpressed p53 protein. There was a significant correlation between presence of gallstones, T stage, grade of tumour and liver invasion with p53 overexpression. There was no significant correlation with other factors studied viz. age, sex, nodal status and histological type.

CONCLUSIONS

The results show a strong association between gallstones and p53 protein overexpression in gallbladder carcinoma. The causal relationship in this association, however, still remains unproven.

Nonrandom chromosomal aberrations and cytogenetic heterogeneity in gallbladder carcinomas

Chromosome banding analysis of 11 short-term cultured gallbladder carcinomas revealed acquired clonal aberrations in seven tumors (five primary and two metastases). Three of these had one clone, whereas the remaining four were cytogenetically heterogeneous, displaying two to seven aberrant clones. Of a total of 21 abnormal clones, 18 had highly complex karyotypes and three exhibited simple numerical deviations. Double minutes and homogeneously staining regions were observed in one and two carcinomas, respectively. To characterize the karyotypic profile of gallbladder cancer more precisely, we have combined the present findings with our three previously reported cases, thereby providing the largest cytogenetic database on this tumor type to date. A total of 287 chromosomal breakpoints were identified, 251 of which were found in the present study. Chromosome 7 was rearranged most frequently, followed by chromosomes 1, 3, 11, 6, 5, and 8. The bands preferentially involved were 1p32, 1p36, 1q32, 3p21, 6p21, 7p13, 7q11, 7q32, 19p13, 19q13, and 22q13. Nine recurrent abnormalities could, for the first time, be identified in gallbladder carcinoma: del(3)(p13), i(5)(p10), del(6)(q13), del(9)(p13), del(16)(q22), del(17)(p11), i(17)(q10), del(19)(p13), and i(21)(q10). The most common partial or whole-arm gains involved 3q, 5p, 7p, 7q, 8q, 11q, 13q, and 17q, and the most frequent partial or whole-arm losses affected 3p, 4q, 5q, 9p, 10p, 10q, 11p, 14p, 14q, 15p, 17p, 19p, 21p, 21q, and Xp. These chromosomal aberrations and imbalances provide some starting points for molecular analyses of genomic regions that may harbor genes of pathogenetic importance in gallbladder carcinogenesis. Genes Chromosomes Cancer 26:312-321, 1999.

p53 tumor suppressor gene mutations in transformed cutaneous T-cell lymphoma: a study of 12 cases

The transformation of cutaneous T-cell lymphoma (t-CTCL) is an uncommon phenomenon that is associated with histopathologic changes and follows an aggressive course. The factors contributing to this transformation are poorly understood. The aim of this study was to analyze the p53 status in t-CTCL and to correlate it with disease outcome. The p53 status was investigated by immunohistochemistry, single-strand conformation polymorphism (SSCP) and DNA sequencing in 12 patients with t-CTCL. Eight mutations were detected; including four in exon 5, one in exon 6 and three in exon 7. Five were point mutations and three were deletions. Paired samples from nontransformed patch and plaque lesions showed no p53 over-expression. Eight disease-related deaths were reported, six to 23 months after transformation, all of which had p53 mutations. Three other patients with wild phenotype (WT-p53) were last reported alive with the disease 19-33 months after transformation (p < 0.0002). One other case had a p53 mutation but a short period of follow-up. Our results suggest that phenotypic changes of t-CTCL are frequently associated with genotype alterations in the p53 gene. Because 70% of the mutations detected were either G to C transversions or deletions, nucleotide-pairing mismatch and not DNA damage by UVB represents a likely mechanism for mutagenesis. Furthermore, the data may help in the design of gene transfer therapies that target the p53 molecule.

K-ras codon 12 and p53 mutations in biopsy specimens and bile from biliary tract cancers

To evaluate whether it is useful for diagnosis to detect K-ras and p53 mutations in biopsy specimens and bile of biliary tract lesions, 12 cholangiocarcinomas (CC), eight cases of cholangitis, seven gallbladder carcinomas (GBC), seven gallbladder cholesterol polyps, four cases of adenomyomatosis of the gallbladder and five cases of cholecystitis were examined. K-ras and p53 mutations in bile were detected by a two-step polymerase chain reaction (PCR) and nested PCR-single-strand conformation polymorphism (SSCP) analysis. In addition, p53 protein expression in biopsy specimens from CC were examined by immunostaining. K-ras mutations at codon 12 were detected in 50% of CC and 57.1% of GBC in both biopsy specimens and bile. The incidence of p53 mutations was 33.3% in CC and 42.9% in GBC. p53 protein overexpression was observed in 60% CC biopsy specimens. In contrast, K-ras and p53 abnormalities were not detected in any non-neoplastic biliary tract lesion. K-ras and p53 mutations in biliary tract cancers showed the same mutation patterns in spite of differences in the collection methods used between bile and biopsy specimens or surgically resected tissue. Genetic analysis of K-ras and p53 mutations in biopsy specimens and bile may be useful for the diagnosis of biliary tract cancers, although it may be effectively limited to patients with advanced disease.

Correlation of p53 protein expression with gene mutation in gall-bladder carcinomas

The correlation of p53 protein expression and p53 mutation of 33 gall-bladder carcinomas was studied according to the depth of invasion and grade of cytological atypia. Overexpression of p53 protein was detected by immunostaining in seven (70.0%) of 10 intramucosal and in 16 (69.6%) of 23 invasive carcinomas. p53 mutation was detected in five (71.4%) of the seven intramucosal carcinomas with overexpression and in eight (50.0%) of the 16 invasive cancers with overexpression and in one (10%) of the 10 non-overexpressing carcinomas at exons 5-8 by nested polymerase chain reaction-single-strand conformation polymorphism. The overexpression of p53 protein was present in nine (56.3%) of 16 low-grade carcinomas and in 14 (82.3%) of 17 high-grade carcinomas. In cases of overexpression, p53 mutation was detectable in four (44.4%) of nine low-grade and in nine (64.3%) of 14 high-grade carcinomas. In total, p53 mutation was verified in 56.5% (13/23) of cases involving protein overexpression and in 10% (1/10) of cases of non-overexpression. The sensitivity of p53 mutation was 56.5% (13/23), the specificity was 90.0% (9/10) and the validity was 1.47. In conclusion, our study indicates that p53 protein overexpression correlates well with gene mutation and that p53 alteration may be related to increasing grade of cytologic atypia of carcinomas.

p53 and HER-2/neu overexpression in ovarian borderline tumors

OBJECTIVE

To study p53 and HER-2/neu expression in borderline ovarian tumors (BLOT) by assessing their frequency, coexpression, and relationship to histologic type, FIGO stage, tumor recurrence, and survival.

METHODS

Forty-two patients with confirmed BLOT (25 serous, 13 mucinous, and 4 seromucinous) were followed for 1.5 to 14 years (mean, 6.3). Thirty (71%) patients had FIGO stage I and 12 (29%) had FIGO stage III disease. Paraffin-embedded sections from the 42 BLOT, 5 normal ovaries, and 10 benign ovarian cystadenomas were stained using monoclonal antibodies against human p53 (DAKO-p53, DAKO, Denmark) and HER-2/neu (C-erB-2, Triton, Parkway, CA). Positive staining was semiquantitated depending on the number of positively stained tumor cells. p53 and HER-2/neu overexpressions were correlated to each other, to histologic subtype, stage, tumor recurrence, and survival.

RESULTS

None of the patients had tumor recurrence. The 5- and 10-year disease-free survival was 100%. None of the normal ovaries or ovarian cystadenomas demonstrated overexpression of p53 or HER-2/neu. Ten (24%) BLOT demonstrated overexpression of p53 and 9 (21%) demonstrated overexpression of HER-2/neu. HER-2/neu overexpression was significantly greater in stage III than in stage I tumors (P = 0.0157). Seromucinous BLOT demonstrated significantly greater p53 overexpression compared with other histologic subtypes (P = 0.030). Coexpression of p53 and HER-2/neu occurred in 4 patients (9.5%). There was no significant correlation between the overexpression of p53 and HER-2/neu (P = 0.180) and no significant relationship between p53 and HER-2/neu overexpression and the presence of microinvasion, ability to perform optimal cytoreductive surgery, tumor recurrence, or survival.

CONCLUSIONS

p53 and HER-2/neu overexpression occurred in about 20-25% of BLOT overall and more commonly in seromucinous and advanced stage tumors. Coexpression occurred in 9.5% of the cases with no significant correlation between the expression of p53 and HER-2/neu.

Spontaneous apoptosis in gallbladder carcinoma. Relationships with clinicopathologic factors, expression of E-cadherin, bcl-2 protooncogene, and p53 oncosuppressor gene

BACKGROUND

Although valuable information regarding spontaneous apoptosis in various human cancers has recently been obtained, spontaneous apoptosis in carcinoma of the gallbladder has not been studied.

METHODS

Apoptotic cells were visualized using the nick end labeling method in 49 cases of gallbladder carcinoma. The relationships between frequency of apoptosis, which was expressed as the maximal apoptotic index (MAI), and clinicopathologic factors, immunoreactivity of E-cadherin (E-CD), bcl-2 protooncogene, and p53 oncosuppressor gene were investigated.

RESULTS

MAI was significantly correlated with the maximum dimension of the tumor (P = 0.020) and high T category (P = 0.034). A closer correlation between high MAI and high T category was observed in E-CD positive cases (P = 0.0035), whereas no such correlation was evident in E-CD negative cases (P = 0.536). No relationship was observed between MAI and age, sex, histology, grading, stromal volume, venous or lymphatic permeation, and lymph node status. Overexpression of bcl-2 and p53 was observed in 18.4% (9 of 49) and 34.7% (17 of 49) of the cases, respectively, and there was a positive correlation between bcl-2 and p53 (P = 0.035). No notable relationship was observed between apoptosis and overexpression of bcl-2 or p53.

CONCLUSIONS

These results indicate that the frequency of apoptosis may increase with the progression of gallbladder carcinoma, and in this process, cell-to-cell interaction may affect the cancer's capacity to undergo apoptosis. Oncogenic changes of bcl-2 and p53 may play a role in tumorigenesis of gallbladder carcinoma, but such changes were not correlated with spontaneous apoptosis.

APC, K-ras codon 12 mutations and p53 gene expression in carcinoma and adenoma of the gall-bladder suggest two genetic pathways in gall-bladder carcinogenesis

Current histopathological evidence suggests that gall-bladder cancer has two main morphological pathways for its development: de novo (ab initio) origin and adenoma-carcinoma sequence. In order to investigate the genetic difference between them, APC mutations were examined by RNase protection analysis, K-ras mutations by nested polymerase chain reaction-restriction fragment length polymorphism analysis, and p53 gene overexpression by immunohisto-chemical analysis in both tumors and benign lesions of the gall-bladder. Overexpression of the p53 gene was detected in 105 of 164 (64%) de novo carcinomas regardless of size and depth of invasion, but not in 16 tumors of carcinoma-in-pyloric-gland-type adenoma, or in 51 adenomas (47 pyloric gland-type and 4 intestinal-type). K-ras codon 12 mutation was detected in 4 of 40 (10%) de novo carcinomas, all four being associated with p53 gene overexpression, but not in 12 tumors of carcinoma in adenoma or 16 adenomas (14 pyloric gland-type and 2 intestinal-type). APC mutation was not found in 16 de novo carcinomas or the one pyloric gland-type adenoma examined. These results suggest that there are two distinct genetic pathways in gall-bladder carcinogenesis; that is, de novo carcinoma develops from a predominant p53 alteration with low K-ras mutation, and carcinoma-in-pyloric-gland-type adenoma develops from p53-, K-ras-, and APC-gene-unrelated, as yet unknown, alteration.

Expression of p53 in adenocarcinoma of the gallbladder and bile ducts

Point mutation of the p53 tumor suppressor gene appears to be an important event in tumor development and progression, and overexpression of the p53 gene product has been widely studied in a variety of neoplasms. Some point mutations of the p53 gene lead to an increase in half-life in the gene product, which accumulates in the nucleus and can be detected by immunohistochemical means. We studied overexpression of p53 protein in specimens from 12 patients with adenocarcinoma of the gallbladder, two gallbladders with epithelial dysplasia without carcinoma, eight carcinomas of the common bile duct, 13 hilar cholangiocarcinomas, and six peripheral cholangiocarcinomas. The monoclonal antibody Ab-2 (Oncogene Science) was used in conjunction with citrate microwave antigen retrieval. Nuclear staining was scored as positive (graded 1 to 3, depending on number of positive nuclei) or negative. Overexpression of p53 protein was present in 7/12 (58%) gallbladder carcinomas, and was seen more often in moderately or poorly differentiated tumors. Intramucosal carcinoma adjacent to invasive carcinoma was positive in three cases, although fewer cells stained than in the carcinoma. Two cases of low-grade dysplasia not associated with carcinoma were negative. Expression of p53 was not an independent prognostic factor when survival was related to grade and stage of tumor. Three of eight (38%) common bile duct carcinomas and 5/13 (38%) hilar cholangiocarcinomas were positive for p53. Slightly fewer (2/6, 33%) peripheral cholangiocarcinomas were positive. No difference in survival relative to p53 expression was demonstrated.

p53 protein overexpression in gallbladder carcinoma and its precursor lesions: an immunohistochemical study

Gallbladder carcinoma is one of the most frequent neoplasms diagnosed in Chile. Although the premalignant lesions have been extensively studied and are well characterized, there is only limited information about the genetic abnormalities that might be important in the pathogenesis of gallbladder carcinoma or that might have prognostic implications. The present study evaluates the immunohistochemical expression of p53 protein in premalignant lesions and invasive carcinoma of the gallbladder, and correlates the p53 expression with histological type, grade of differentiation, and level of invasion of the tumor. The authors studied the immunohistochemical p53 protein overexpression in 52 gallbladder carcinomas, 47 carcinomas in situ (CISs), 34 dysplasias, and 10 specimens with chronic cholecystitis containing normal and metaplastic epithelium. A semiquantitative scoring system was used to assess the p53 reactivity. p53 overexpression was found in 34 of 52 (65.4%) carcinomas, 21 of 47 (44.7%) CISs, and 11 of 34 (32.4%) dysplasias. There were no significant differences in p53 expression in premalignant lesions associated with invasive carcinoma and those that were not. Normal and metaplastic epithelium did not overexpress p53 protein. In adenocarcinomas, no correlation was found between p53 protein overexpression and histological subtype, grade of differentiation, or level of invasion. The high incidence of p53 overexpression in gallbladder carcinoma and its presence in dysplasia, even in specimens without invasive carcinomas, suggests that this abnormality is an important and early event in the pathogenesis of the tumor. The progressively increasing incidence of p53 overexpression observed from premalignant lesions to invasive tumor provides additional support to the view that this is the usual route for the development of infiltrating gallbladder carcinoma.

K-ras and p53 mutations in stage I gallbladder carcinoma with an anomalous junction of the pancreaticobiliary duct

BACKGROUND

An anomalous junction of the pancreaticobiliary duct (AJPBD) was thought to be an important risk factor for gallbladder carcinoma in Japan. In this report, we compared K-ras and p53 mutations in Stage I gallbladder carcinomas (GC) of patients with AJPBD with those in patients without AJPBD:

METHODS

We examined 6 GC of patients with AJPBD and 20 GC of patients without AJPBD: Immunohistochemistry was performed for p53 protein. K-ras and p53 mutations were examined using genomic DNA extracted from the cancer regions. The methods of polymerase chain reaction (PCR) single strand conformation polymorphism analysis were performed for mutations in exons 5-8 of p53. The methods of PCR restriction fragment length polymorphism were performed for mutation in codon 12 of K-ras.

RESULTS

p53 positivity was 67% in GC of patients with AJPBD and 65% in GC of patients without AJPBD: p53 mutations were found in exons 7 and 8 in GC of patients with AJPBD and in exons 5, 6, and 7 in GC of patients without AJPBD: The incidence of K-ras mutation in GC of patients with AJPBD (50%) was greater than that in patients without AJPBD (6%) (P < 0.05).

CONCLUSIONS

These results suggest that K-ras mutation may be important in the early stage of carcinogenesis of the gallbladder mucosa with AJPBD, and that p53 mutations may also contribute to the early stage of carcinogenesis of the gallbladder mucosa, regardless of AJPBD:

Direct tumorigenic conversion of human gallbladder carcinoma cells by v-src but not by activated c-H-ras oncogene

The roles of activated ras and src oncogene products in the acquisition of fully neoplastic phenotype by human gallbladder adenocarcinoma cells were investigated by co-transfecting non-tumorigenic HAG-I human gallbladder carcinoma cells with the pSV2neo plasmid and a plasmid carrying either activated c-H-ras or v-src oncogene. G418-resistant clones were isolated and assessed for the acquisition of anchorage-independent growth potential. Neither the 10 established clones transfected with pSV2neo alone nor the 17 clones transfected with activated c-H-ras, including 4 clones expressing the mutated p21H-ras protein, could form colonies in soft agar. By contrast, out of 10 clones transfected with v-src, 2 formed colonies in soft agar and produced tumors in athymic nude mice, the resulting progressive neoplasms being poorly differentiated adenocarcinomas. These tumorigenic clones were shown to have v-src DNA and mRNA levels with p60v-src protein, but there were no significant chromosomal alterations following tumorigenic conversion. Moreover, herbimycin A, a selective src-kinase inhibitor, markedly reduced clonogenic growth of these cells in soft agar rather than monolayer growth, suggesting that anchorage-independent growth of the v-src-transformed HAG-I cells might be driven directly by p60v-src kinase activity. Taken together, our data suggest that the fully neoplastic conversion of HAG-I cells depends on src-related tyrosine-kinase activity, but not solely on the function mediated by activated ras, thus providing evidence of an src-related signaling pathway for the acquisition of tumorigenic potential by human gallbladder adenocarcinoma cells.